The performance of a network node (such as the base station of a mobile telecommunications network) is affected by external factors, such as environmental factors and the load on the node. When operating parameters of the node are adjustable, this allows the node to be optimized for use. It is known to adjust a parameter value of a node from a first value to a second value and to compare the performance of the node over periods when the different parameter values were applied. However, in known arrangements, which are described in more detail below, the exact time at which a parameter value is changed is not known, and this means that it is not possible to determine precisely whether changes in the recorded performance data are due to a change in the parameter value or due to some external factor. Further, known arrangements tend to apply a particular parameter value for an extended period of time, such as one week. This is unsatisfactory because an external factor that affects the node, such as a traffic jam, may be present during the week that the parameter was set to a first value but may be absent during the week that the parameter was set to the second value. This results in the performance data being misleading.
Accordingly, it would be desirable to provide a system for operating a network that addresses the above-noted issues.